Tuesday, May 21, 2019

The origin of Fennoscandinavian and Baltic N in Kola Peninsula? Part II update 2

Additional data:

After so many studies handling Baltic and Finnic people, I would like to see new Scandinavian research.  We have very few of them.

A few words about methods

Most studies use Nganasans as a Siberian reference despite of the European population being tested.  So, if we consider Nganasans to be closest to Finno-Ugric people, we can mistake with other Europeans, because the relationship between Finns and Nganasans makes them a special case. We may have done a wrong premise in a European wide analysis. Especially, if we assume that N1c1 came to Finland via Norhteastern route, through Kola Peninsula, we should not consider Nganasans as Siberian in general, because it is in that case a special case and cannot represent Siberians in general.  Maybe Ukrainians had some other Siberian connections, we don't know if we use only Siberian references suggested being close only FU-people, in other words Nganasans. Likely Ukrainians have not that admixture, but the method we use has to be neutral.  Do we want to use some edge reference instead of mainline references?  Edge references fit best with population next to the edge.  Another relevant outcome is that the more distant reference groups are from the tested one, the smaller the difference between relative reference groups is when compared to the population under test.  This means that valid Siberian references in same test should give same amount admixture for all tested populations without known Siberian admixture (European references).  If not they are not valid references.  But then, it is totally another issue if we use qpAdm, which tries to use non-relative method, but it is another story.  Let's look it in practice.

I ran a supervised admixture model assigning 10 Siberian groups to 3 West European groups.  The result shows that a genetic connection between Nganasans and West Europeans is possible, despite of the Nganasan tendency to be least admixed Siberians in unsupervised models. Nearest for Nganasans of those three are Germans, followed by Spaniards and English Cornwall is least Nganasan.  The fact is that Admixture is a relative method, which cannot get negative admixture values (qpAdm can).



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